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enter image description here I applied the Sine stripes as the emission Textures to the spherical object. As you can see, the difference between where the emission is on (white) and off (black) is not apparent enough, not as apparent as the Area Light’s light.

enter image description here So, how do I make the emission to have the same sharpness? Thank you!

Blender file: https://blenderartists.org/uploads/short-url/ibtkmDVAnKW7bFz5lZ2Xr8NjAnE.blend

Orange Cat
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1 Answers1

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Use the Dot Product of the Geometry's normal and incoming vector. Clamp it above some high value ($0.9$ - $0.99$) to only emit in the direction of the normal. Mix that with the original emission to simulate a lamp surface that scatters the light in all directions additionally. (Otherwise it will appear black to most camera rays.)

node setup

Leander
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